1. Tiny living organisms that are too small to be seen without a microscope, such as bacteria, viruses, fungi, and protozoans.
Usage: Plural form; singular is 'microorganism'.; Commonly used in biology, medicine, and food science.

Examples

• Microorganisms in soil help break down dead plants and return nutrients to the earth.
• Scientists study microorganisms to understand how diseases spread.
• Some microorganisms are beneficial, while others can cause infections.
• Microorganisms are found in almost every environment on Earth, from hot springs to frozen tundra.
• Proper food storage prevents harmful microorganisms from multiplying.
• The human gut contains trillions of microorganisms that aid digestion.
• Microorganisms were first observed under early microscopes in the 1600s.